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In this work, multiplicative cyberattacks targeting the sensor-controller communication link of a process control system are considered. The interdependence of detectability of an attack with respect to a general class of residual-based detection schemes and the control parameters is characterized. Exploiting this dependence, a controller screening methodology that may be used to incorporate cyberattack detectability into the standard controller design criteria is presented. Using a chemical process example, the application of the controller design screening to a nonlinear process is demonstrated.
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Controller Switching-Enabled Active Detection of Multiplicative Cyberattacks on Process Control Systems
This work focuses on the problem of enhancing cyberattack detection capabilities in process control systems subject to multiplicative cyberattacks. First, the relationship between closed-loop stability and attack detectability with respect to a class of residual-based detection schemes is rigorously analyzed. The results are used to identify a set of controller parameters (called "attack-sensitive" controller parameters) under which an attack can destabilize the closed-loop system. The selection of attack-sensitive controller parameters can enhance the ability to detect attacks, but can also degrade the performance of the attack-free closed-loop system. To balance this trade-off, a novel active attack detection methodology employing controller parameter switching between the nominal controller parameters (chosen on the basis of standard control design criteria) and the attack-sensitive controller parameters, is developed. The proposed methodology is applied to a chemical process example to demonstrate its ability to detect multiplicative sensor-controller communication link attacks.
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- Award ID(s):
- 2137281
- PAR ID:
- 10416875
- Date Published:
- Journal Name:
- American Control Conference
- Page Range / eLocation ID:
- 2473 to 2478
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.23919/ACC53348.2022.9867804
